Two Intel 8080 microprocesor chips, 1970s.
© Science Museum / Science & Society Picture Library
Introduced by Intel in 1974, the 8080 microprocesor was the first microprocesor powerful enough to build a computer around. It was used in the Altair 8800, one of the first personal computers, which was available to buy in kit form for 397 dollars. This computer became so popular, that within months, tens of thousands had been sold, creating the first PC back orders in history.